aria-pressed-changes-button-role.html

<!DOCTYPE html>
<button id="test"></button>
<script>
  var go_passes = [
    () => document.getElementById("test").setAttribute("aria-pressed", "true"),
    () => document.getElementById("test").removeAttribute("aria-pressed")
  ];

  var current_pass = 0;
  function go() {
    go_passes[current_pass++].call();
    return current_pass < go_passes.length;
  }

</script>

chromium/content/test/data/accessibility/event/aria-pressed-changes-button-role.html